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A273171 Triangle for numerators of coefficients for integrated odd powers of cos(x) in terms sin((2*m+1)*x). 2
1, 3, 1, 5, 5, 1, 35, 7, 7, 1, 63, 7, 9, 9, 1, 231, 55, 33, 55, 11, 1, 429, 429, 143, 143, 13, 13, 1, 6435, 5005, 3003, 195, 455, 105, 15, 1, 12155, 2431, 1547, 221, 595, 85, 17, 17, 1, 46189, 12597, 12597, 969, 323, 969, 969, 57, 19, 1, 88179, 146965, 20349, 14535, 2261, 20349, 5985, 133, 105, 21, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
The triangle for the denominators is given in A273172.
Int(cos^(2*n+1)(x), x) = Sum_{m = 0..n} R(n, m)*sin((2*m+1)*x), n >= 0, with the rational triangle a(n, m)/A273172(n, m).
For the rational triangle for the odd powers of cos see A244420/A244421. See also the odd-indexed rows of A273496.
The signed rational triangle S(n, m) = R(n, m)*(-1)^(m+1) appears in the formula
Int(sin^(2*n+1)(x), x) = Sum_{m = 0..n} S(n, m)*cos((2*m+1)*x), n >= 0,
REFERENCES
I. S. Gradstein and I. M. Ryshik, Tables of series, products , and integrals, Volume 1, Verlag Harri Deutsch, 1981, pp. 168-169, 2.513 1 and 4.
LINKS
FORMULA
a(n, m) = numerator(R(n, m)) with the rationals R(n, m) = (1/2^(2*n)) * binomial(2*n+1, n-m)/(2*m+1) for m = 0, ..., n, n >= 0. See the Gradstein-Ryshik reference (where the sin arguments are falling).
EXAMPLE
The triangle a(n, m) begins:
n\m 0 1 2 3 4 5 6 7 8 9
0: 1
1: 3 1
2: 5 5 1
3: 35 7 7 1
4: 63 7 9 9 1
5: 231 55 33 55 11 1
6: 429 429 143 143 13 13 1
7: 6435 5005 3003 195 455 105 15 1
8: 12155 2431 1547 221 595 85 17 17 1
9: 46189 12597 12597 969 323 969 969 57 19 1
...
row 10: 88179 146965 20349 14535 2261 20349 5985 133 105 21 1,
...
The rational triangle R(n, m) begins:
n\m 0 1 2 3 4 ...
0: 1/1
1: 3/4 1/12
2: 5/8 5/48 1/80
3: 35/64 7/64 7/320 1/448
4: 63/128 7/64 9/320 9/1792 1/2304
...
row 5: 231/512 55/512 33/1024 55/7168 11/9216 1/11264,
row 6: 429/1024 429/4096 143/4096 143/14336 13/6144 13/45056 1/53248,
row 7: 6435/16384 5005/49152 3003/81920 195/16384 455/147456 105/180224 15/212992 1/245760,
row 8: 12155/32768 2431/24576 1547/40960 221/16384 595/147456 85/90112 17/106496 17/983040 1/1114112,
row 9: 46189/131072 12597/131072 12597/327680 969/65536 323/65536 969/720896 969/3407872 57/1310720 19/4456448 1/4980736,
row 10: 88179/262144 146965/1572864 20349/524288 14535/917504 2261/393216 20349/11534336 5985/13631488 133/1572864 105/8912896 21/19922944 1/22020096.
...
n = 3: Int(cos^7(x), x) = (35/64)*sin(x) + (7/64)*sin(3*x) + (7/320)*sin(5*x) + (1/448)*sin(7*x). Gradstein-Rhyshik, p. 169, 2.513 16.
Int(sin^7(x), x) = -(35/64)*cos(x) + (7/64)*cos(3*x) - (7/320)*cos(5*x) + (1/448)*cos(7*x). Gradstein-Rhyshik, p. 169, 2.513 10.
MATHEMATICA
T[MaxN_] := Function[{n}, With[{exp = Expand[(1/2)^(2 n + 1) (Exp[I x] + Exp[-I x])^(2 n + 1)]}, 2/(2 # + 1) Coefficient[exp, Exp[I (2 # + 1) x]] & /@ Range[0, n]]][#] & /@ Range[0, MaxN];
T[5] // ColumnForm (* Bradley Klee, Jun 14 2016 *)
PROG
(PARI) a(n, m) = numerator((1/2^(2*n))*binomial(2*n+1, n-m)/(2*m+1));
tabl(nn) = for (n=0, nn, for (k=0, n, print1(a(n, k), ", ")); print()); \\ Michel Marcus, Jun 19 2016
CROSSREFS
Sequence in context: A209560 A211977 A072919 * A244420 A274513 A104489
KEYWORD
nonn,tabl,frac,easy
AUTHOR
Wolfdieter Lang, Jun 13 2016
STATUS
approved

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Last modified April 16 05:35 EDT 2024. Contains 371697 sequences. (Running on oeis4.)